Why Can We Never Be Sure That a Sample Represents

Multiple Choice

Why can we never be sure that a sample represents a population?

A) Random selection never works the way it is supposed to work.
B) Samples created by random selection are almost never perfectly representative.
C) A random sample may poorly represent a population,or it may accurately represent a different population.
D) If selection is conducted correctly,samples always accurately represent the populations they are supposed to represent.